COVID-19 in Pakistan: A national analysis of five pandemic waves

ObjectivesThe COVID-19 pandemic showed distinct waves where cases ebbed and flowed. While each country had slight, nuanced differences, lessons from each wave with country-specific details provides important lessons for prevention, understanding medical outcomes and the role of vaccines. This paper compares key characteristics from the five different COVID-19 waves in Pakistan. MethodsWe used specific criteria to define COVID-19 waves, and key variables such as COVID-19 tests, cases, and deaths with their rates of change to the peak and then to the trough were used to draw descriptive comparisons. Additionally, a linear regression model estimated daily new COVID-19 deaths in Pakistan. ResultsPakistan saw five distinct waves, each of which displayed the typical topology of a complete infectious disease epidemic. The time from wave-start to peak became progressively shorter, and from wave-peak to trough, progressively longer. Each wave appears to also be getting shorter, except for wave 4, which lasted longer than wave 3. A one percent increase in vaccinations increased daily new COVID-19 deaths by 0.10% (95% CI: 0.01, 0.20) in wave 4 and decreased deaths by 0.38% (95% CI: -0.67, -0.08) in wave 5. ConclusionEach wave displayed distinct characteristics that must be interpreted in the context of the level of response and the variant driving the epidemic. Key indicators suggest that COVID-19 preventive measures kept pace with the disease. Waves 1 and 2 were mainly about prevention and learning how to clinically manage patients. Vaccination started late during Wave 3 and its impact became apparent on hospitalizations and deaths in Wave 5. The impact of highly virulent strains Alpha/B1.1.7 and Delta/B.1.617.2 variants during Wave 3 and milder but more infectious Omicron/BA.5.2.1.7 are apparent.